4-chloro-3,5-dimethylpyridine hydrochloride

ABSTRACT

USE OF 3 METHYL OR 3.5-DIMETHYL 4-HALO PYRIDINE OR PYRIDINE N-OXIDES AS SOIL NEMATOCIDES. AN EXAMPLE IS 4CHLORO-3-METHYLPYRIDINE N-OXIDE. THIS ABSTRACT IS NOT INTENDED TO BE A DESCRIPTION OF THE INVENTION DEFINED BY THE CLAIMS.

United States Patent 3,573,315 4-CHLOR0-3,5-DIMETHYLPYRIDINEHYDROCHLORIDE Martin Jacob Handele and Johannes Kuipers, Weesp, and

Kobus Wellinga, Eindhoven, Netherlands, assigmors to US. PhilipsCorporation, New York, N.Y. No Drawing. Original application Aug. 11,1967, Ser. No. 659,856, now Patent No. 3,449,497, dated June 10, 1969.Divided and this application Nov. 14, 1968, Ser. No. 794,453

' Claims priority, applicatgogi Ngzherlands, Aug. 13, 1966,

14 Int. Cl. C07d 31/24 US. Cl. 260-290 1 Claim ABSTRACT OF THEDISCLOSURE Use of 3 methyl or 3.5-dimethyl 4-halo pyridine or pyridineN-oxides as soil nematocides. An example is 4- chloro-3-methylpyridineN-oxide. This abstract is not intended to be a description of theinvention defined by the claims.

Rg-L

wherein R is chlorine or bromine, R is hydrogen or alkyl of 1-4 carbonatoms particularly methyl, R is alkyl of 1-4 carbon atoms particularlymethyl and n is 0 or 1.

:Examples of these compounds are:

(l) 4chloro-3-methylpyridine hydrochloride. (2)4-chloro-3-methylpyridine-N-oxide.

(3) 4-chloro-3,S-dimethylpyridine hydrochloride. (4)4-chlor0-3,5-dimethylpyridine-N-oxide.

These compounds are known with the exception of 4-chloro-3,5-dimethylpyridine hydrochloride.

Applicants have found that the compounds according to the invention areactive against plant parasitic nematodes and that by means ofcompositions prepared on the basis of these compounds, the nematodepopulations occurring in the soil can be inactivated so that they causelittle or no damage to the plant crops.

The compounds have proved particularly active against nonfree-livingnematodes for example Meloidogyne species. The control ofMeloidogyne-nematodes is of particular importance because the organismsof this species cause damage to a very large number of host plants amongwhich are: cotton, tobacco, red pepper, tomato, flowers, fruit trees(notably lemon and grapefruit), tea, hemp, soya-bean, sugar beets andolives.

In particular, the 4-chloro-3-methylpyridine hydrochloride has proved tobe particularly active.

The compounds of the invention are particularly useful as a preventivemeans against the occurrence of damage to plants by nematodes.

It therefore is of advantage to treat the soil with the compound beforethere is planting or sowing in the soil.

In most cases a waiting period of from 5 to 14 days is suflicient beforeplanting takes place. In some cases the soil may be treatedsimultaneously with or after the planting. This is particularly so whenthe plants were already protected in a different manner to a certainextent against nematode infestation or when the plants are damaged bynematodes only at a later stage of the development.

One of the advantages of the compounds according to the invention isthat the substances are only very slightly phytotoxic, both with respectto the above-soil and sub-soil parts of the plants.

The effects according to the invention can be obtained with acomparatively low dosage. Thus concentrations of 5-150 kg./hectareparticularly 10-80 kg./hectare formulated in the usual manner aregenerally effective dosages, that is to say, as a solution of thecompound in water, in a mineral oil, possibly mixed with awater-miscible solvent, for example, a lower aliphatic alcohol. 'Inaddition, the substance may be processed into granules. Various formsare possible, for example, porous granules (for example, attaclay,pumice), mineral non-porous granules (for ex ample sand, ground marl),organic granules (for example, coffee grounds, stems of tobacco leaves),or granules which can be produced by compression of powdered mineralsand/or organic substances. Other possibilities are: invert emulsion,miscible oil, paste, wettable powders, water-soluble powder, dust oraerosols.

The invention will now be described in greater detail with reference tothe following examples:

EXAMPLES (1) 4-chloro-3-methylpyridine-N-oxide was dissolved in water,to which also an emulsifier was added according to the followingformulation:

Percent Active substance 45.0 Emulsifier (alkylaryl) 1.5 Distilled water(polyglycol ether) 53.5

Percent Active substance 15.0 Water 18.3 Attaclay granules, diameter0.5-2 mms. 66.7

In a dosage of 40 kg. of active substance per hectare, a cover of 4granules per cm. was obtained.

(3) 4-chloro-3-methylpyridine hydrochloride coated with a thin layer ofa fatty alcohol was impregnated into attaclay granules according to thecomposition:

. Percent Active substance 15.0 Water 18.3 Attaclay granules, diameter0.5-2 mms. 64.2

Fatty alcohols (technical quality) consisting of:

710% of myristyl alcohol, 43-45% cetyl alcohol and 40-50% of stearylalcohol 2.5

In a dosage of 40 kg. of active substance per hectare a cover ofapproximately 4 parts per cm. was obtained.

(4) 4-chloro-3-methylpyridine-N-oxide was dispersed in water and thenimpregnated on dry coffee granules as follows:

Percent Active substance 5.0 Water 10.0 Dried coffee granules, diameter0.5-2 mms 85.0

In a dosage of 40 kg. per hectare a cover of 12 granules per m? wasobtained.

(5) A wettable powder was prepared having the following composition:

Percent 4-chloro-3,S-dimethylpyridine hydrochloride 75.0 Mineral orsoluble salt, for example, urea 22.5 Surface active substance 2.5

(6) Granules were prepared having the following composition:

Percent 4-chloro-3 ,5-dimethylpyridine-N-oxide 25 .0 sulphide-lye powder10.0 Water 5 .0 Dolomite 60.0

The compositions of the invention may be introduced into the soil inseveral different ways.

According to one method, a composition in a finely divided form isbrought on the soil which is then dug, harrowed or ploughed. For mostpurposes, it is sufficient when the soil is cultivated to a depth offrom to 50 cm. In rainy periods the mechanical cultivation of the soilmay be omitted and it may be left to the influence of the rain to bringthe active substance deeper into the soil. As a rule it is not necessaryto repeat the whole treatment, but if required, a quantity of from 10 to80 kgms. of active substance per hectare may again be brought on thesoil after a few weeks. It has not been found that in this manner damageof any significance is done to vegetation grown up in the meantime.

According to another method, a composition containing the activesubstance is provided in the rows of furrows destined for the vegetationto be sown or planted. Although in this manner deactivation of thenematodes over the total surface of the soil is not obtained, aprotection against the nematode activity can be obtained in this mannerat the places where this is desirable since the nematodes move at acomparatively low rate.

The active compounds according to the invention may also be mixed withother pesticides, notably, soil fungicides, for example, chloropikrine,tetramethyl thiouram disulphide, pentachloronitrobenzene, zineb, maneb,8-hydroxy-quinoline, organic tinand mercury compounds, triphenyl tinhydroxide or the acetate or butyrate thereof, in addition monomethyldithiocarbamic acid sodium salt, in addition with soil insecticides, forexample, chlorinated hydrocarbons (dieldrin) endrin, toxaphan andhexachlorocyclohexane, or, finally with artificial manures for examplephosphates.

(7) g. of 4-chloro-3-methylpyridine-N-oxide were mixed according toexample number 1, 2.6 g. of alkylaryl-polyglycolether (Triton X 114")and 96 g. of water. The preparation was diluted with water to 80.1.

Three other solutions were prepared in quite the same manner differingonly in the quantity of 4-chloro-3-methylpyridine-N-oxide. Thequantities were 40, 20 and 0 g. (blank) respectively.

Each solution was evenly sprayed on implanted plots of 10 ml. each.According to the soil samples, the soil was infested with Meloz'dogyneincognita var. acritd (on an average 1500 larvae per 500 g. of soil).The degree of infestation was substantially the same for all the plots.Right'after spraying, each plot was cultivated to a depth of 25 cm. 1week after the soil treatment, young tomato plants (var. Bonny Best),approximately 8 cm. high, were planted on each plot.

10 weeks after planting, the weight of the plants and the degree of rootgall formation were determined.

On the plots where a 4-chloro-S-methylpyridine-N- oxide containingsolution had been sprayed, a considerably smaller root gall formationwas found than on the blank plot where the systems of roots were badlyinfested.

(8) 4-chloro-3-methylpyridine hydrochloride: Units of 1 kg. of soilinfested with Meloz'dopy incogniza var. acrita, were mixed with 25, 6%and 0 mgs. of 4-chloro- 3-methyl-pyridine hydrochloride dissolved in 20'mls. of water. The units of treated soil were then transferred to glassl-litre pots, sealed and stored for 1 week at a temperature ofapproximately 22 C. After this period the units of soil were transferredto plastic pouches which, likewise sealed, were stored for 1 week at atemperature of approximately 22 C. These pouches with soil were then dugin a stape (27 C.) and planted with young tomato plants (approximately 8cms. high). 6 weeks after planting the root infestation was determined.A strong reduction of the root infestation was found with respect to acontrol experiment.

(9) 6.3 g. (0.04 mol) of 4-chloro-3,5-dimethyl-N oxide were dissolved in50 mls. of chloroform. A solution of 11 g. (0.08 mol) of phosphorustrichloride in 25 ml. of chloroform was added dropwise to the solutionwhile stirring, during which the temperature rose. After the addition,the solution was refluxed for 30 minutes. Gaseous hydrogen chloride wasled in the resulting solution to saturation. The chloroform wasevaporated in vacuo for the greater part after which the hydrochlorideof 4-chloro-3,5-dimethyl pyridine was precipitated by the addition ofdiethyl ether. Yield 5.3 g. (74.4%) meltingpoint 232.5 (sublimation).

While we have described our invention in connection with specificembodiments and applications, other modifications thereof will bereadily apparent to those skilled in this art without departing from thespirit and scope of the invention as defined in the appended claim.

What we claim is:

1. 4-chloro-3,S-dimethyl-pyridine hydrochloride.

No references cited.

HENRY R. JILES, Primary Examiner H. I. MOATZ, Assistant Examiner

